An epilepsy that is characterized by onset of seizures in the neonatal period or first months of life, with seizures showing favorable response to treatment with activated vitamin B6 (pyridoxal 5-prime-phosphate; PLP) and/or pyridoxine, and that has_material_basis_in homozygous or compound heterozygous mutation in the PROSC gene (PLPBP) on chromosome 8p11.